Wearable and Marker-Less Sensing for Load and Technique Quantification in Combat Sports: A Scoping Review, with Fencing as an Illustrative Case

Combat sports require measurement systems that tolerate contact and protective equipment. Following JBI and PRISMA-ScR guidance, this scoping review mapped how wearable, marker-less, and equipment-embedded sensors have been used to quantify load, physiological response, and technique in boxing, judo, wrestling, taekwondo, and fencing, and what measurement-property evidence accompanies their outputs. PubMed and IEEE Xplore (2015–2026) were searched and supplemented by citation searching; a second reviewer screened a random 20% sample (κ = 0.75). We included 222 reports, 39 of them charted from abstracts, which most often used physiological wearables, followed by inertial and equipment-embedded sensors. Only 44 reports (20%) presented strong evidence for the analysed output (criterion agreement, between-day reliability, verified event detection or testing on unseen athletes), and 28 (13%) weak evidence only. Of 38 machine-learning evaluations, 12 tested athletes not used for training. Four reports (three in boxing) paired head-impact exposure with an acute health endpoint and 11 recorded mechanical surrogates only; none linked sensor exposure to subsequent injury. We propose a 14-item reporting checklist adapted from existing guidance.